Add to cart MDDI SU Williams CPITN-C Probe 3.5/5.5/8.5/11.5 DE (20pk) £19.45 SU Williams 10mm/CPITN-C Probes 3.5/5.5/8.5/11.5 DE – The MDDI range of sterile, single-use dental instruments are designed to assist in reducing both cross contamination risks and reprocessing costs from your surgery. Each box contains 20 individually wrapped instruments.